jasder
/
runc
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Merge pull request #1249 from datawolf/small-refactor 

small refactor
This commit is contained in:
Qiang Huang 2017-01-13 02:04:59 -06:00 committed by GitHub
parent 29008b871d 4732f46fd9
commit a9610f2c02
1 changed files with 5 additions and 27 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

32
libcontainer/cgroups/utils.go
View File

@ -23,36 +23,14 @@ const (
// https://www.kernel.org/doc/Documentation/cgroup-v1/cgroups.txt
func FindCgroupMountpoint(subsystem string) (string, error) {
// We are not using mount.GetMounts() because it's super-inefficient,
// parsing it directly sped up x10 times because of not using Sscanf.
// It was one of two major performance drawbacks in container start.
if !isSubsystemAvailable(subsystem) {
return "", NewNotFoundError(subsystem)
}
f, err := os.Open("/proc/self/mountinfo")
if err != nil {
return "", err
}
defer f.Close()
scanner := bufio.NewScanner(f)
for scanner.Scan() {
txt := scanner.Text()
fields := strings.Split(txt, " ")
for _, opt := range strings.Split(fields[len(fields)-1], ",") {
if opt == subsystem {
return fields[4], nil
}
}
}
if err := scanner.Err(); err != nil {
return "", err
}
return "", NewNotFoundError(subsystem)
mnt, _, err := FindCgroupMountpointAndRoot(subsystem)
return mnt, err
}
func FindCgroupMountpointAndRoot(subsystem string) (string, string, error) {
// We are not using mount.GetMounts() because it's super-inefficient,
// parsing it directly sped up x10 times because of not using Sscanf.
// It was one of two major performance drawbacks in container start.
if !isSubsystemAvailable(subsystem) {
return "", "", NewNotFoundError(subsystem)
}